How long would blurred vision from botox last ?

Dry eyes: You really shouldn't have blurred vision from Botox injections unless it was done near your eyelids and it has affected your blinking. Poor blink reflex can cause dry eyes. If this is the case, artificial tears should help. The Botox will wear off in 3-4 months. If tears don't help, see your ophthalmologist.

Botox blurred vision: I would add that Botox injections near the eyelids can cause issues with eyelid closure and tear film production (lasting up to 3 mos) but some studies have also shown systemic side effects (such as temporary blurred vision after injections in the palms for sweating) that can last for weeks to months. The simple fact is, although safe in general, there can be short-lived side effects.

Botox side effect: If the Botox has diffused into the orbital muscles, then the blurred vision may last several weeks to months, talk to your treating doctor about your concerns if they persist. My belief is that if the person performing the "procedure" is not able to handle the complications, they should not be doing the procedure. Hopefully your provider was an experienced doctor.